GMC SIERRA DENALI 2003 Owners Manual

Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen
if the road is wet enough and
you’re going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can
if
your tires do not have much tread or if the pressure in
one or more is low. It can happen
if a lot of water is
standing on the road. If you can see reflections
from trees, telephone poles or other vehicles, and
raindrops “dimple” the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just isn’t a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice: If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage your engine. Never drive through water that is
slightly lower than the underbody
of your vehicle. If
you can’t avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowhg W=+er
--m
Flowing or rushing water creates strong forces.
If you try to drive through flowing water, as you
might at a low water crossing, your vehicle can
be carried away.
As little as six inches of
flowing water can carry away
a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Don’t ignore police
warning signs, and otherwise be very cautious
about trying to drive through flowing water.
Some Other Rainy Weather Tips
Turn on your low-beam headlamps - not just your
parking lamps
- to help make you more visible to
others.
Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
Have good tires with proper tread depth. See
Tires
on page 5-6 I.
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City Driving One of the biggest problems with city streets is the
amount of traffic on them. You’ll want to watch out for
what the other drivers are doing and pay attention
to traffic signals.
Here are ways to increase your safety in city driving:
Know the best way to get to where you are
going. Get a city map and plan your trip into
an unknown part of the city just as you would for a
cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You’ll save time and energy.
See the next part, “Freeway Driving.”
Treat a green light as a warning signal. A traffic
light is there because the corner is busy enough
to need
it. When a light turns green, and just before
you start to move, check both ways for vehicles
that have not cleared the intersection or may
be running the red light.
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Freeway Driving
Mile for mile, freeways (also called thruways, parkways,
expressways, turnpikes or superhighways) are the
safest of all roads. But they have their own special rules. The most
important advice on freeway driving is: Keep
up with traffic and keep to the right. Drive at the
same speed most of the other drivers are driving.
Too-fast or too-slow driving breaks a smooth traffic flow.
Treat the left lane on a freeway as a passing lane.
At the entrance, there is usually a ramp that leads to
the freeway.
If you have a clear view of the freeway as
you drive along the entrance ramp, you should begin
to check traffic. Try to determine where you expect
to blend with the flow. Try to merge into the gap at close
to the prevailing speed. Switch on your turn signal,
check your mirrors and glance over your shoulder as
often as necessary. Try to blend smoothly with the
traffic flow.
Once you are on the freeway, adjust your speed to the
posted limit
or to the prevailing rate if it’s slower.
Stay in the right lane unless you want to pass.
Before changing lanes, check your mirrors. Then use
your turn signal.
Just before you leave the lane, glance quickly over your
shoulder to make sure there isn’t another vehicle in
your “blind” spot.
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Once you are moving on the freeway, make certain you
allow a reasonable following distance. Expect to
move slightly slower at night.
When you want
to leave the freeway, move to the
proper lane well in advance.
If you miss your exit, do
not, under any circumstances, stop and back up. Drive
on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted.
Reduce your speed according to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds, you may tend
to think you are
going slower than you actually are.
Before Leaving on a Long Trip
Make sure you’re ready. Try to be well rested. If you
must start when you’re not fresh
- such as after a day’s
work
- don’t plan to make too many miles that first
part of the journey. Wear comfortable clothing and shoes
you can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it’s ready to go. If it needs
service, have it done before starting out.
Of course,
you’ll find experienced and able service experts
in dealerships all across North America. They’ll be
ready and willing to help
if you need it.
Here are some things you can check before a trip:
e
e e
e
e
e
e
Windshield Washer Fluid: Is the reservior full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked
all levels?
Lamps: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe,
trouble-free trip.
Is the tread good enough for
long-distance driving? Are the tires all inflated to the
recommended pressure?
Weather Forecasts: What’s the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
Maps: Do you have up-to-date maps?
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Highway Hypnosis
Is there actually such a condition as "highway
hypnosis"? Or is it just plain falling asleep at the wheel?
Call it highway hypnosis, lack of awareness, or
whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush
of the
wind against the vehicle that can make you sleepy. Don't
let it happen to you!
If it does, your vehicle can leave
the road in
less than a second, and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
Keep your eyes moving. Scan the road ahead and
comfortably cool interior.
to the
sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat
or rolling terrain.
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If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See
Operating
Your All-Wheel-Drive Vehicle
Off Paved Roads on
page
4-16 for information about driving off-road.
Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard
on mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
If you don’t I R down, your -____ 3s COL- ge-
so hot that they wouldn’t work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep downhill slope. Coasting
UVwnlll..
..I NEUTRAL (N) G. .... h the
ignition
off is dangerous. Your brakes will have
to do all the work
of slowing down. They could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none
going down a
hill. You could crash. Always
have your engine running and your vehicle in
gear when you go downhill.
Know how to go uphill. You may want to shift down to
a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
roads in hills or mountains. Don’t swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could
be something in your lane, like a stalled car or an
accident.
You may see highway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones, a falling rocks area or
winding roads. Be alert to these and take appropriate
action.
Stay in your own lane when driving on two-lane
4-37

Winter Driving Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies in
your vehicle.
Include an ice scraper, a small brush or broom, a
supply of windshield washer fluid, a rag, some winter
outer clothing,
a small shovel, a flashlight, a red
cloth and reflective warning triangles. And,
if you will be
driving under severe conditions, include
a small bag
of sand, a piece of old carpet or a couple of burlap bags
to help provide traction. Be sure you properly secure
these items
in your vehicle.
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Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction. the
least traction of all. You can get wet ice when it’s
about freezing (32°F; OOC) and freezing rain begins
to fall. Try to avoid driving on wet ice until salt and sand
crews can get there.
However,
if there is snow or ice between your tires and Whatever the condition - smooth ice, packed, blowing
the road, you can have a very slippery situation.
You’ll have a lot less traction or “grip” and will need to
be very careful. Accelerate gently. Try not to break the fragile traction.
If
or loose snow - drive with caution.
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
m
What’s the worst time for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer Your
anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road.
Even though you have an anti-lock braking system,
you’ll want to begin stopping sooner than you would on
dry pavement. See
Braking on page 4-6.
Allow greater following distance on any slippery
road.
0 Watch for slippery spots. The road might be fine
until you hit a spot that’s covered with ice. On
an otherwise clear road, ice patches may appear
in
shaded areas where the sun can’t reach: around
clumps
of trees, behind buildings or under bridges.
Sometimes the surface of a curve or an overpass
may remain icy when the surrounding roads
are clear.
If you see a patch of ice ahead of you,
brake before you are on it. Try not to brake
while you’re actually on the ice, and avoid sudden
steering maneuvers.
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If You’re Caught in a Blizzard
If you are stopped by heavy snow, you could be in a
serious situation. You should probably stay with
your vehicle unless you know for sure that you are near
help and you can hike through the snow. Here are
some things to do to summon help and keep yourself
and your passengers safe:
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Turn on your hazard flashers.
Tie a red cloth to your vehicle to alert police that
you’ve been stopped by the snow.
Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make
body insulators from newspapers, burlap bags, rags,
floor mats
- anything you can wrap around
yourself or tuck under your clothing to keep warm.
. _-. I:. .
You can run the engine to keep warm, but be careful.

Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You can’t see
it or
smell
it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow
doesn’t collect there.
Open a window just a little on the side of the
vehicle that’s away from the wind. This will
help keep
CO out. Run your
engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged.
You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine
off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold.
But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or
so until
help comes.
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